Effect of Small Molecule Compounds on the Pyrolysis Behavior of Coal

Document Type : Research Article


1 College of Chemical Engineering and Technology, Shanxi Key Laboratory of High Value Utilization of Coal Gangue, Taiyuan University of Science and Technology, Taiyuan 030024, P.R. CHINA

2 Jin Zhong University, College of Chemistry and Chemical Engineering, Yuci 030619, P.R. CHINA

3 Lin Yi Institutes of Industrial Technology, Linyi 276000, P.R. CHINA


The effect of small molecule compounds on the pyrolysis behavior of coal is discussed by comparing TG and DTG curves of Yanzhou coal and its tetrahydrofuran (THF) extracted residual in this paper. Based on the thermal gravimetric analysis of Yanzhou coal and its THF-extracted residual, it is revealed that part of the chemical bonds are weakened after the small molecular compound is extracted from coal, which promotes the pyrolysis of its THF-extracted residual. The optimum reaction temperature is 490 oC for the high-temperature fast liquefaction of the THF-extracted residual. The maximum temperature of weight-loss rate for Yanzhou Coal and its THF extracted residual is 439 oC and 437 oC, respectively. The liquefaction reaction temperature of them is 389-490 oC and 380-525 oC, respectively. The results we studied could give some help to the further perfection of the theory of the pyrolysis behavior of coal, and its application. And it is further helpful to study the mechanism of the theory of the pyrolysis behavior of coal.


Main Subjects

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